Is there a callback event for when the selected signals of a Bus Selector block change?

I'm trying to perform an action to add some metadata in to a model annotation related to the signals selected by a bus selector.

Is there a callback event that will be triggered when the Bus Selector's Block Parameter dialog is closed or when the list of selected signals is updated?

I've tried CloseFcn for the bus selector but this isn't triggered when the dialog is closed.

The best options I have found so far are to bind my function to the MoveFcn for the block AND the PreSaveFcn.